Controlled actuation of a reactive metal

ABSTRACT

Apparatus and methods for initiating the reaction of a reactive metal element of a downhole device. An example method introduces the downhole device into a wellbore; wherein the downhole device comprises the reactive metal element; wherein the reactive metal element has a first volume; and wherein the reactive metal element is separated from a reaction-inducing fluid by a frangible casing. The frangible casing is removed and the reactive metal element is contacted with the reaction-inducing fluid to produce a reaction product having a second volume greater than the first volume.

TECHNICAL FIELD

The present disclosure relates to the use of a reactive metal element,and more particularly, to methods and apparatus for controlling theactuation of a reactive metal element.

BACKGROUND

In some wellbore operations, a swellable material may be used forsealing and/or anchoring. A few examples of apparatus that utilizeswellable materials include packers, sealing elements, and linerhangers. A packer may be used to seal and isolate a wellbore zone.Expandable sealing elements may be used for a variety of wellboreapplications including forming annular seals and zonal isolation. Linersmay be suspended from a casing string or set cement layer with a linerhanger. The liner hanger anchors and seals to the interior of the casingstring or set cement layer and suspends the liner below the casingstring or set cement layer.

Some species of swellable materials comprise elastomers. Elastomers suchas rubber may swell when contacted with a swell-inducing fluid. Theswell-inducing fluid may diffuse into the elastomer where a portion ofthe fluid may be retained within the internal structure of theelastomer. Swellable materials such as elastomers may be limited to usein specific wellbore environments (e.g., those without high salinityand/or high temperatures). In some wellbore operations, it may beimportant to time the actuation of the swellable material to preventpremature actuation. The present disclosure provides improved apparatusand methods for controlling the actuation of a reactive metal element inwellbore applications.

BRIEF DESCRIPTION OF THE DRAWINGS

Illustrative examples of the present disclosure are described in detailbelow with reference to the attached drawing figures, which areincorporated by reference herein, and wherein:

FIG. 1 is an illustration of a reactive metal element shaped into alattice structure in accordance with the examples disclosed herein;

FIG. 2 is a cross-section of an example downhole device comprising areactive metal element in accordance with the examples disclosed herein;

FIG. 3 is a cross-section of the example downhole device of FIG. 2 afterbreaking of the frangible casing in accordance with the examplesdisclosed herein;

FIG. 4 is a cross-section of the example downhole device of FIGS. 1 and2 with an additional modification in accordance with the examplesdisclosed herein;

FIG. 5 is a cross-section of another example downhole device comprisinga reactive metal element in accordance with the examples disclosedherein;

FIG. 6 is a cross-section of the example downhole device of FIG. 5 afterbreaking of the frangible casing in accordance with the examplesdisclosed herein;

FIG. 7 is a cross-section of an example setting tool comprising areactive metal element in accordance with the examples disclosed herein;and

FIG. 8 is a cross-section of the example setting tool of FIG. 7 afterbreaking of the frangible casing in accordance with the examplesdisclosed herein.

The illustrated figures are only exemplary and are not intended toassert or imply any limitation with regard to the environment,architecture, design, or process in which different examples may beimplemented.

DETAILED DESCRIPTION

The present disclosure relates to the use of a reactive metal element,and more particularly, to methods and apparatus for controlling theactuation of a reactive metal element.

In the following detailed description of several illustrative examples,reference is made to the accompanying drawings that form a part hereof,and in which is shown by way of illustration examples that may bepracticed. These examples are described in sufficient detail to enablethose skilled in the art to practice them, and it is to be understoodthat other examples may be utilized, and that logical structural,mechanical, electrical, and chemical changes may be made withoutdeparting from the spirit or scope of the disclosed examples. To avoiddetail not necessary to enable those skilled in the art to practice theexamples described herein, the description may omit certain informationknown to those skilled in the art. The following detailed descriptionis, therefore, not to be taken in a limiting sense, and the scope of theillustrative examples is defined only by the appended claims.

Unless otherwise indicated, all numbers expressing quantities ofingredients, properties such as molecular weight, reaction conditions,and so forth used in the present specification and associated claims areto be understood as being modified in all instances by the term “about.”Accordingly, unless indicated to the contrary, the numerical parametersset forth in the following specification and attached claims areapproximations that may vary depending upon the desired propertiessought to be obtained by the examples of the present disclosure. At thevery least, and not as an attempt to limit the application of thedoctrine of equivalents to the scope of the claim, each numericalparameter should at least be construed in light of the number ofreported significant digits and by applying ordinary roundingtechniques. It should be noted that when “about” is at the beginning ofa numerical list, “about” modifies each number of the numerical list.Further, in some numerical listings of ranges some lower limits listedmay be greater than some upper limits listed. One skilled in the artwill recognize that the selected subset will require the selection of anupper limit in excess of the selected lower limit.

Unless otherwise specified, any use of any form of the terms “connect,”“engage,” “couple,” “attach,” or any other term describing aninteraction between elements is not meant to limit the interaction todirect interaction between the elements and may also include indirectinteraction between the elements described. Further, any use of any formof the terms “connect,” “engage,” “couple,” “attach,” or any other termdescribing an interaction between elements includes items integrallyformed together without the aid of extraneous fasteners or joiningdevices. In the following discussion and in the claims, the terms“including” and “comprising” are used in an open-ended fashion, and thusshould be interpreted to mean “including, but not limited to.” Unlessotherwise indicated, as used throughout this document, “or” does notrequire mutual exclusivity.

The terms uphole and downhole may be used to refer to the location ofvarious components relative to the bottom or end of a well. For example,a first component described as uphole from a second component may befurther away from the end of the well than the second component.Similarly, a first component described as being downhole from a secondcomponent may be located closer to the end of the well than the secondcomponent.

Examples of the methods and apparatus described relate to the use of areactive metal element, and more particularly, to methods and apparatusfor controlling the actuation of a reactive metal element. The reactivemetal element comprises a reactive metal which, after reaction, providesan expansion of its metal to seal, anchor, and/or fill voids in theannular space. The reactive metal provides this expansion aftercontacting a specific reaction-inducing fluid, such as a brine, where itproduces a reaction product having a larger volume than the basereactive metal reactant. This increase in metal volume of the reactionproduct provides for an expansion of the metal reaction product into anyadjacent void space. This expansion may be sufficient to seal theadjacent void space, to anchor a conduit proximate the adjacent voidspace, and/or to simply fill the adjacent void space. The reactionproduct solidifies within the adjacent void space in order to performfor further wellbore operations. The formation of the reaction productsresults in the volumetric expansion of the reactive metal elementallowing for an improvement in zonal isolation. The solidified reactionproducts also improve the anchoring of any surrounding conduit,positioning it in the wellbore and allowing for secure suspension.Advantageously, the reactive metal elements may be used in a variety ofwellbore applications. Yet a further advantage is that the reactivemetal elements provide expansion in high-salinity and/orhigh-temperature environments. An additional advantage is that thereactive metal elements comprise a wide variety of metals and metalalloys and react upon contact with reaction-inducing fluids, including avariety of wellbore fluids. The reactive metal elements may be used asreplacements for other types of expandable elements (e.g., elastomericelements), or they may be used in combination with other types ofexpandable elements. One other advantage is that in some examples, thereactive metal elements may be placed on existing conduits withoutimpact to or adjustment of the conduit outer diameter or exteriorprofile to accommodate the reactive metal element. In some examples, thereactive metal elements are free of elastomeric materials and may beusable in wellbore environments where elastomeric materials may be proneto breakdown.

In some wellbore applications, the timing of the actuation of thereactive metal elements may be important. As such, controlling the timeof contact of the reaction metal element and the reaction-inducing fluidmay prevent premature actuation of the reactive metal element such thatthe reactive metal element is not actuated until in the desired positionand at the desired time. Advantageously, the reactive metal element maybe sealed from contact with the reaction-inducing fluid by a barrierwith a controlled rupturing. As a further advantage, the reactive metalelement may be interspersed with a non-reactive fluid which wouldprevent reaction until dispersed by the inflowing reaction-inducingfluid.

The reactive metals expand by undergoing a reaction in the presence of areaction-inducing fluid (e.g., a brine) to form a reaction product(e.g., metal hydroxides). The resulting reaction products occupy morevolumetric space relative to the base reactive metal reactant.

This difference in volume allows the reactive metal element to expand tofill void space at the interface of the reactive metal element and anyadjacent surfaces. It is to be understood that the use of the term“fill” does not necessarily mean a complete filling of the void space,and that the reaction product may partially fill the void space in someexamples. Magnesium may be used to illustrate the volumetric expansionof the reactive metal as it undergoes reaction with thereaction-inducing fluid. A mole of magnesium has a molar mass of 24g/mol and a density of 1.74 g/cm³, resulting in a volume of 13.8cm³/mol. Magnesium hydroxide, the reaction product of magnesium and anaqueous reaction-inducing fluid, has a molar mass of 60 g/mol and adensity of 2.34 g/cm³, resulting in a volume of 25.6 cm³/mol. Themagnesium hydroxide volume of 25.6 cm³/mol is an 85% increase in volumeover the 13.8 cm³/mol volume of the mole of magnesium. As anotherexample, a mole of calcium has a molar mass of 40 g/mol and a density of1.54 g/cm³, resulting in a volume of 26.0 cm³/mol. Calcium hydroxide,the reaction product of calcium and an aqueous reaction-inducing fluid,has a molar mass of 76 g/mol and a density of 2.21 g/cm³, resulting in avolume of 34.4 cm³/mol. The calcium hydroxide volume of 34.4 cm³/mol isa 32% increase in volume over the 26.0 cm³/mol volume of the mole ofcalcium. As yet another example, a mole of aluminum has a molar mass of27 g/mol and a density of 2.7 g/cm³, resulting in a volume of 10.0cm³/mol. Aluminum hydroxide, the reaction product of aluminum and anaqueous reaction-inducing fluid, has a molar mass of 63 g/mol and adensity of 2.42 g/cm³, resulting in a volume of 26 cm³/mol. The aluminumhydroxide volume of 26 cm³/mol is a 160% increase in volume over the 10cm³/mol volume of the mole of aluminum. The reactive metal may compriseany metal or metal alloy that undergoes a reaction to form a reactionproduct having a greater volume than the base reactive metal or alloyreactant.

The reactive metals undergo a chemical transformation whereby the metalschemically react with the reaction-inducing fluid, and upon reactionform a metal hydroxide that is the principal component of the expandedreactive metal element. The solidified metal hydroxide is larger involume than the base reactive metal, allowing for expansion into theannular space around the reactive metal element (e.g., an adjacent voidspace).

Examples of suitable metals for the reactive metal include, but are notlimited to, magnesium, calcium, aluminum, tin, zinc, beryllium, barium,manganese, or any combination thereof. Preferred metals includemagnesium, calcium, and aluminum.

Examples of suitable metal alloys for the reactive metal include, butare not limited to, alloys of magnesium, calcium, aluminum, tin, zinc,beryllium, barium, manganese, or any combination thereof. Preferredmetal alloys include alloys of magnesium-zinc, magnesium-aluminum,calcium-magnesium, or aluminum-copper. In some examples, the metalalloys may comprise alloyed elements that are not metallic. Examples ofthese non-metallic elements include, but are not limited to, graphite,carbon, silicon, boron nitride, and the like. In some examples, themetal is alloyed to increase reactivity and/or to control the formationof oxides.

In some examples, the metal alloy is also alloyed with a dopant metalthat promotes corrosion or inhibits passivation and thus increaseshydroxide formation. Examples of dopant metals include, but are notlimited to, nickel, iron, copper, carbon, titanium, gallium, mercury,cobalt, iridium, gold, palladium, or any combination thereof.

In some examples, the reactive metal comprises an oxide. As an example,calcium oxide reacts with water in an energetic reaction to producecalcium hydroxide. One mole of calcium oxide occupies 9.5 cm³ whereasone mole of calcium hydroxide occupies 34.4 cm³. This is a 260%volumetric expansion of the mole of calcium oxide relative to the moleof calcium hydroxide. Examples of metal oxides suitable for the reactivemetal may include, but are not limited to, oxides of any metalsdisclosed herein, including magnesium, calcium, aluminum, iron, nickel,copper, chromium, tin, zinc, lead, beryllium, barium, gallium, indium,bismuth, titanium, manganese, cobalt, or any combination thereof.

It is to be understood that the selected reactive metal is chosen suchthat the formed reaction product does not dissolve or otherwise degradein the reaction-inducing fluid in a manner that prevents itssolidification in a void space. As such, the use of metals or metalalloys for the reactive metal that form relatively insoluble reactionproducts in the reaction-inducing fluid may be preferred. As an example,the magnesium hydroxide and calcium hydroxide reaction products havevery low solubility in water. As an alternative or an addition, thereactive metal element may be positioned and configured in a way thatconstrains the degradation of the reactive metal element in thereaction-inducing fluid due to the geometry of the area in which thereactive metal element is disposed. This may result in reduced exposureof the reactive metal element to the reaction-inducing fluid, but mayalso reduce degradation of the reaction product of the reactive metalelement, thereby prolonging the life of the reaction product in the voidspace. As an example, the volume of the area in which the reactive metalelement is disposed may be less than the potential expansion volume ofthe volume of reactive metal disposed in said area. In some examples,this volume of area may be less than as much as 50% of the expansionvolume of reactive metal. Alternatively, this volume of area may be lessthan 90% of the expansion volume of reactive metal. As anotheralternative, this volume of area may be less than 80% of the expansionvolume of reactive metal. As another alternative, this volume of areamay be less than 70% of the expansion volume of reactive metal. Asanother alternative, this volume of area may be less than 60% of theexpansion volume of reactive metal. In a specific example, a portion ofthe reactive metal element may be disposed in a recess within theconduit to restrict the exposure area to only the surface portion of thereactive metal element that is not disposed in the recess.

In some examples, the formed reaction products of the reactive metalreaction may be dehydrated under sufficient pressure. For example, if ametal hydroxide is under sufficient contact pressure and resists furthermovement induced by additional hydroxide formation, the elevatedpressure may induce dehydration of the metal hydroxide to form the metaloxide. As an example, magnesium hydroxide may be dehydrated undersufficient pressure to form magnesium oxide and water. As anotherexample, calcium hydroxide may be dehydrated under sufficient pressureto form calcium oxide and water. As yet another example, aluminumhydroxide may be dehydrated under sufficient pressure to form aluminumoxide and water.

The reactive metal elements may be formed in a solid solution process, apowder metallurgy process, or through any other method as would beapparent to one of ordinary skill in the art. Regardless of the methodof manufacture, the reactive metal elements may be slipped over theconduit and held in place via any sufficient method. The reactive metalelements may be placed over the conduit in one solid piece or inmultiple discrete pieces. Once in place, the reactive metal element maybe held in position with end rings, stamped rings, retaining rings,fasteners, adhesives, set screws, swedging, or any other such method forretaining the reactive metal element in position. In some alternativeexamples, the reactive metal element may not be held in position and mayslide freely on the exterior of the tubular. As discussed above, thereactive metal elements may be formed and shaped to fit over existingconduits and may not require modification of the outer diameter orprofile of the liner hanger in some examples. Alternatively, the conduitmay be manufactured to comprise a recess in which the reactive metalelement may be disposed. The recess may be of sufficient dimensions andgeometry to retain the reactive metal elements in the recess. Inalternative examples, the reactive metal element may be cast onto theconduit. In some alternative examples, the diameter of the reactivemetal element may be reduced (e.g., by swaging) when disposed on theconduit. In some examples, the reactive metal elements may be disposedover the length of the conduit (e.g., the singular conduit joint of theconduit string that is threaded or coupled to other conduit joints toform a conduit string). In alternative examples, the reactive metalelement may be placed on only a portion of the conduit joint. In someexamples, the reactive metal elements may be placed on all conduitjoints to form continuous covering of the conduit string. In otherexamples, the reactive metal elements may be placed on only some of theconduit joints of the conduit string (e.g., at locations where cementassurance issues may occur).

In some optional examples, the reactive metal element may be shaped suchas to increase the available surface area for reaction. Such shapes maycomprise pieces, pellets, latices, and the like. FIG. 1 is anillustration of a lattice-shaped reactive metal element. In someoptional examples, a foam may be used as the lattice. In furtheroptional embodiments, a non-reactive material such as non-reactive fluidor non-reactive solid may be dispersed within the shaped reactive metalelement to delay contact with the reaction-inducing fluid. For example,the voids within the lattice and the exterior of the lattice may becovered with a non-reactive material. In other example, the exterior andinterstitial spaces between pieces or pellets of the reactive metalelement may be filled with the non-reactive material. Examples of thenon-reactive material may include non-reactive fluids including, but notlimited to, air, nitrogen, carbon dioxide, liquid hydrocarbons, liquidwaxes, oleaginous fluids, distilled water, glycerin, alcohol, or anycombination. The non-reactive fluid may be displaced via fluid pressurefrom the reaction-inducing fluid upon contact and/or fluid pressure fromthe hydrogen gas produced by the reaction of the reactive metal and thereaction-inducing fluid as the reaction process begins on a portion ofthe reactive metal element. Examples of the non-reactive material mayinclude non-reactive solids including, but not limited to, polylacticacid, polyglycolic acid, plastics, solid waxes, or any combination. Thenon-reactive solid material may be degraded via time and/or increasingwellbore temperature. The degraded remnants may then be displaced byfluid pressure from the reaction-inducing fluid upon contact and/orfluid pressure from the hydrogen gas produced by the reaction of thereactive metal and the reaction-inducing fluid as the reaction processbegins on a portion of the reactive metal element. Upon displacement ofthe non-reactive material, the reactive metal of the reactive metalelement may contact the reaction-inducing fluid and may react to performthe desired wellbore operation.

In some optional examples, the reactive metal element may include aremovable barrier coating. The removable barrier coating may be used tocover the exterior surfaces of the reactive metal element and preventcontact of the reactive metal with the reaction-inducing fluid. Theremovable barrier coating may be removed after other wellbore operationsare completed. The removable barrier coating may be used to delayreaction and/or prevent premature expansion with the reactive metalelement. Examples of the removable barrier coating include, but are notlimited to, any species of plastic shell, organic shell, paint,dissolvable coatings (e.g., solid magnesium compounds or an aliphaticpolyester), a meltable material (e.g., with a melting temperature lessthan 550° F.), or any combination thereof. When desired, the removablebarrier coating may be removed from the reactive metal element with anysufficient method. For example, the removable barrier coating may beremoved through dissolution, a phase change induced by changingtemperature, corrosion, hydrolysis, melting, or the removable barriercoating may be time-delayed and degrade after a desired time underspecific wellbore conditions.

In some optional examples, a removable casing may cover the exteriorsurfaces of the reactive metal element and prevent contact of thereactive metal with the reaction-inducing fluid. The removable casingmay be removed after other wellbore operations are completed. Theremovable casing may be used to delay reaction and/or prevent prematureexpansion of the reactive metal element. Examples of the removablecasing include, but are not limited to, frangible casings that areeasily broken, degraded, destroyed, melted, shattered, etc. Thefrangible casing may be removed through forces such as torque, tension,puncturing, impacting, degradation from fluid contact and/or wellboreconditions such as pressure and/or temperature, or a combination offorces. For example, the frangible casing may rip under strain from asufficient applied axial force. The frangible casing may comprise anyfrangible material sufficient for breaking, ripping, shattering,degrading, melting, etc. Examples of the frangible material include, butare not limited to, sufficiently thin metals; sufficiently brittlepolymers such as acrylic, polystyrene, etc.; cellulosic materials suchas paper and waxed paper; ceramic materials; and the like. The degree ofthinness and/or brittleness of the frangible material will be determinedby the species of material chosen and the potential force available tobreak the frangible casing. One of ordinary skill in the art will bereadily able to determine the potential force available and thus thepotential material properties necessary to remove the frangible casingupon application of said force. In some additional optional examples,the frangible casing may be stressed during manufacture through theinclusion of stress risers such as cracks, grooves, etc. The stressrisers may allow for a relatively lower applied force to break thefrangible casing and may also allow for frangible casing to break in aconsistent pattern. Upon removal, the reactive metal of the reactivemetal element may contact the reaction-inducing fluid and may react toperform the desired wellbore operation.

In some optional examples, the reactive metal element may include anadditive which may be added to the reactive metal element duringmanufacture as a part of the composition, or the additive may be coatedonto the reactive metal element after manufacturing. The additive mayalter one or more properties of the reactive metal element. For example,the additive may improve expansion, add texturing, improve bonding,improve gripping, etc. Examples of the additive include, but are notlimited to, any species of ceramic, elastomer, glass, non-reactingmetal, the like, or any combination thereof.

The reactive metal element may be used to expand into any void spacesthat are proximate to the reactive metal elements. Without limitation,the reactive metal elements may be used to fill any voids in adjacentspace, which may include annular spaces adjacent to a conduit, as wellas defects in cement sheaths such as cracks within a cement sheath,channels formed from gas channeling through a cement sheath, microannuliformed between the cement sheath and the conduit which may be formedfrom temperature cycling, stress load cycling, conduit shrinkage, etc.

As described above, the reactive metal elements comprise reactive metalsand as such, they are non-elastomeric materials. As non-elastomericmaterials, the reactive metal elements do not possess elasticity, andtherefore, they may irreversibly expand when contacted with areaction-inducing fluid. The reactive metal elements may not return totheir original size or shape even after the reaction-inducing fluid isremoved from contact.

Generally, the reaction-inducing fluid induces a reaction in thereactive metal to form a reaction product that occupies more space thanthe unreacted reactive metal. Examples of the reaction-inducing fluidinclude, but are not limited to, saltwater (e.g., water containing oneor more salts dissolved therein), brine (e.g., saturated saltwater,which may be produced from subterranean formations), seawater, or anycombination thereof. Generally, the reaction-inducing fluid may be fromany source provided that the fluid does not contain an excess ofcompounds that may undesirably affect other components in the sealingelement. In the case of saltwater, brines, and seawater, thereaction-inducing fluid may comprise a monovalent salt or a divalentsalt. Suitable monovalent salts may include, for example, sodiumchloride salt, sodium bromide salt, potassium chloride salt, potassiumbromide salt, and the like. Suitable divalent salt can include, forexample, magnesium chloride salt, calcium chloride salt, calcium bromidesalt, and the like. In some examples, the salinity of thereaction-inducing fluid may exceed 10%. Advantageously, the reactivemetal elements of the present disclosure may not be impacted by contactwith high-salinity fluids. One of ordinary skill in the art, with thebenefit of this disclosure, should be readily able to select areaction-inducing fluid for inducing a reaction with the reactive metalelements.

The reactive metal elements may be used in high-temperature formations(e.g., in formations with zones having temperatures equal to orexceeding 350° F.). Advantageously, the use of the reactive metalelements of the present disclosure may not be impacted inhigh-temperature formations. In some examples, the reactive metalelements may be used in both high-temperature formations and withhigh-salinity fluids. In a specific example, a reactive metal elementmay be positioned on a conduit and used to fill a void in a cementsheath after contact with a brine having a salinity of 10% or greaterwhile also being disposed in a wellbore zone having a temperature equalto or exceeding 350° F.

FIG. 2 is a cross-section of an example downhole device, generally 5. Inthis specific example, the downhole device 5 may be a sealing systemsuch as a packer. The downhole device 5 comprises a reactive metalelement 10 disposed within a void space 15. The void space 15 may becarved into the downhole device 5, or the downhole device 5 may bemanufactured to comprise a suitable void space 15. The geometry of thevoid space 15 is designed such that an opening 20 is presented to theexterior of the downhole device 5. The downhole device 5 may be deployedand run in hole until the opening 20 is adjacent an annular space intowhich the reactive metal element 10 is to be deployed upon reaction.Covering at least a portion of the reactive metal element 10 is afrangible casing 25. The frangible casing 25 may cover the portion ofthe reactive metal element 10 exposed to the opening 20 or may covermore of the reactive metal element 10, including covering of theentirety of the reactive metal element 10. The reactive metal element 10may be deployed in a desired shape such as a lattice, pellets, or pieceswithin the void space 15. In some optional examples, a non-reactivematerial may be deployed in the void space 15 and interspersed withinthe reactive metal element 10 to assist in preventing prematurereaction. A sliding piston 30, or other such actuating component, may bedisposed adjacent to the void space 15 containing the reactive metalelement 10. Translation of the sliding piston 30 is prevented by a bodylock ring 35. The body lock ring 35 is exemplary in nature and may besubstituted for any other such locking mechanism so as to preventundesired translation of the sliding piston 30.

FIG. 3 is a cross-section of the example downhole device 5 of FIG. 1after the frangible casing 25 has been broken. When desired for use, thebody lock ring 35 may be disengaged to allow for translation of thesliding piston 30. Translation of the sliding piston 30 may occur as aresult of increasing localized fluid pressure in the wellbore, or may beactuated by hydraulic, mechanical, pneumatic or other such mechanisms aswould be readily apparent to one of ordinary skill in the art. Thesliding piston 30 applies axial pressure to the void space 15 so as tocompress the frangible casing 25 and the reactive metal element 10disposed within. The frangible casing 25 is broken into pieces therebyallowing portions of the reactive metal element 10 to be exposed to theexterior annular space adjacent the opening 20. In some examples, thecompression may push the pieces, pellets, and/or lattice structure ofthe reactive metal element 10 into the annular space. The exposedreactive metal of the reactive metal element 10 may now be in a positionto contact a circulating reaction-inducing fluid. Upon contact with thereaction-inducing fluid, the reactive metal within the reactive metalelement 10 will react to form the reaction product, thereby providing afilling expansion into any adjacent space contactable by the reactionproduct to perform a sealing, filling, or anchoring operation asdesired.

FIG. 4 is a cross-section of the example downhole device 5, of FIGS. 2and 3 with modification. In this specific example, the downhole device 5may be a sealing system such as a packer. The downhole device 5comprises a reactive metal element 10 disposed within a void space 15.The void space 15 may be carved into the downhole device 5 or thedownhole device 5 may be manufactured to comprise a suitable void space15. The geometry of the void space 15 is designed such that an opening20 is presented to the exterior of the downhole device 5. The downholedevice 5 may be deployed and run in hole until the opening 20 isadjacent an annular space into which the reactive metal element 10 is tobe deployed upon reaction. Covering at least a portion of the reactivemetal element 10 is a frangible casing 25. The frangible casing 25 maycover the portion of the reactive metal element 10 exposed to theopening 20 or may cover more of the reactive metal element 10, includingcovering of the entirety of the reactive metal element 10. The reactivemetal element 10 may be deployed in a desired shape such as a lattice,pellets, or pieces within the void space 15. In some optional examples,a non-reactive material may be deployed in the void space 15 andinterspersed within the reactive metal element 10 to assist inpreventing premature reaction. A sliding piston 30, or other suchactuating component, may be disposed adjacent to the void space 15containing the reactive metal element 10. Translation of the slidingpiston 30 is prevented by a body lock ring 35. The body lock ring 35 isexemplary in nature and may be substituted for any other such lockingmechanism so as to prevent undesired translation of the sliding piston30. The interior diameter of the downhole device 5 comprises openings 40that extend starting from a flowpath 45 within the interior of thedownhole 5 through the body of the downhole device 5 and into the voidspace 15. A sliding component 50 (e.g., a sleeve, piston, or othertranslatable member) is disposed within the flowpath 45. The slidingcomponent 50 blocks fluid flow within flowpath 40 and seals flowpath 45with sealing elements 55. When the downhole device 5 is positioned asdesired, the sliding component 50 may be removed allowing for a reactioninducing fluid to enter into openings 40 to allow for expansion andsealing of the reactive metal element 10 within the flowpath 45 as thereactive metal reacts and expands within the flowpath 45. Additionally,the sliding piston 30 may be compressed in some examples to allowsealing, anchoring, etc. as described in FIG. 3 above.

FIG. 5 is a cross-section of an example downhole device, generally 100.In this specific example, the downhole device 100 may be a sealingsystem such as a packer. The downhole device 100 comprises a reactivemetal element 105 disposed within a void space 110. In the illustratedexample, the void space 110 exists between two end rings 115 disposed onthe exterior surface of the body 120 of the downhole device 100. Thegeometry of the void space 110 is designed such that an opening 125 ispresented to the exterior of the downhole device 100. The downholedevice 100 may be deployed and run in hole until the opening 125 isadjacent an annular space into which the reactive metal element 105 isto be deployed upon reaction. Covering at least a portion of thereactive metal element 105 is a frangible casing 130. The frangiblecasing 130 may cover the portion of the reactive metal element 105exposed to the opening 125 or may cover more of the reactive metalelement 105, including covering of the entirety of the reactive metalelement 105. This specific reactive metal element 105 is illustrated asa solid piece and is not a lattice, pellet, or discrete pieces. Adjacentto the reactive metal element 105 is a non-reactive material 140 such asa non-reactive fluid.

FIG. 6 is a cross-section of the example downhole device 100 of FIG. 5after the frangible casing 130 has been broken. When desired for use,axial force may be applied to one or both of the end rings 115 resultingin translation of at least one of the end rings 115 towards the reactivemetal element 105. Translation of the end rings 115 may occur as aresult of increasing localized fluid pressure in the wellbore, or may beactuated by hydraulic, mechanical, pneumatic or other such mechanisms aswould be readily apparent to one of ordinary skill in the art. The endrings 115 apply axial pressure to the void space 110 so as to compressthe frangible casing 130. The frangible casing 130 is broken into piecesthereby allowing portions of the reactive metal element 105 to beexposed to the exterior annular space adjacent the opening 125. Theexposed reactive metal of the reactive metal element 105 may now be in aposition to contact a circulating reaction-inducing fluid. Upon contactwith the reaction-inducing fluid, the reactive metal within the reactivemetal element 105 will react to form the reaction product, therebyproviding a filling expansion into any adjacent space contactable by thereaction product to perform a sealing, filling, or anchoring operationas desired.

FIG. 7 is a cross-section of an example downhole device, generally 200.In this specific example, the downhole device 200 is a setting tool. Thedownhole device 200 comprises a reactive metal element 205 disposed onthe exterior of the downhole device 200. In the illustrated example, thereactive metal element 205 is wedge shaped and moves along its slope asa part of the operation of the downhole device 200. Covering at least aportion of the downhole device 200 is a frangible casing 210. Thefrangible casing 210 covers the portion of the downhole device 200containing the reactive metal element 205. This specific reactive metalelement 205 is illustrated as a solid piece and is not a lattice,pellet, or discrete pieces. A sliding piston 215 or other translatablemember is disposed within the center throughbore of the downhole device200.

FIG. 8 is a cross-section of the example downhole device 200 of FIG. 7after the frangible casing 210 has been broken. When desired for use,axial force may be applied the sliding piston 215 resulting intranslation of the sliding piston 215. Translation of the sliding piston215 may occur as a result of increasing localized fluid pressure in thewellbore, or may be actuated by hydraulic, mechanical, pneumatic orother such mechanisms as would be readily apparent to one of ordinaryskill in the art. The sliding piston 215 applies axial pressure via aflanged or wedged structure 225 which is further translated to thewedge-shaped reactive metal element 205. The reactive metal element 205is then shunted outward radially into the frangible casing 210 which isthen broken into pieces thereby allowing portions of the reactive metalelement 205 to be exposed to any exterior annular space. The exposedreactive metal of the reactive metal element 205 may now be in aposition to contact a circulating reaction-inducing fluid. Upon contactwith the reaction-inducing fluid, the reactive metal within the reactivemetal element 205 will react to form the reaction product, therebyproviding a filling expansion into any adjacent space contactable by thereaction product to perform a sealing, filling, or anchoring operationas desired.

It should be clearly understood that the examples illustrated by FIGS.1-8 are merely general applications of the principles of this disclosurein practice, and a wide variety of other examples are possible.Therefore, the scope of this disclosure is not limited in any manner tothe details of any of the FIGURES described herein.

It is also to be recognized that the disclosed reactive metal elementsmay also directly or indirectly affect the various downhole equipmentand tools that may come into contact with the reactive metal elementsduring operation. Such equipment and tools may include, but are notlimited to: wellbore casing, wellbore liner, completion string, insertstrings, drill string, coiled tubing, slickline, wireline, drill pipe,drill collars, mud motors, downhole motors and/or pumps, surface-mountedmotors and/or pumps, centralizers, turbolizers, scratchers, floats(e.g., shoes, collars, valves, etc.), logging tools and relatedtelemetry equipment, actuators (e.g., electromechanical devices,hydromechanical devices, etc.), sliding sleeves, production sleeves,plugs, screens, filters, flow control devices (e.g., inflow controldevices, autonomous inflow control devices, outflow control devices,etc.), couplings (e.g., electro-hydraulic wet connect, dry connect,inductive coupler, etc.), control lines (e.g., electrical, fiber optic,hydraulic, etc.), surveillance lines, drill bits and reamers, sensors ordistributed sensors, downhole heat exchangers, valves and correspondingactuation devices, tool seals, packers, cement plugs, bridge plugs, andother wellbore isolation devices, or components, and the like. Any ofthese components may be included in the systems generally describedabove and depicted in any of the FIGURES.

Provided are methods for initiating the reaction of a reactive metalelement of a downhole device. An example method comprises introducingthe downhole device into a wellbore; wherein the downhole devicecomprises the reactive metal element; wherein the reactive metal elementhas a first volume; and wherein the reactive metal element is separatedfrom a reaction-inducing fluid by a frangible casing. The method furthercomprises removing the frangible casing and contacting the reactivemetal element with the reaction-inducing fluid to produce a reactionproduct having a second volume greater than the first volume.

Additionally or alternatively, the method may include one or more of thefollowing features individually or in combination. The reactive metalelement may be in the shape of a lattice. The reactive metal element maybe comprised of discrete pieces. The reactive metal element may bedisposed within a void space of the downhole device and a non-reactivematerial may be interspersed within the reactive metal element while thereactive metal element is disposed within the void space. Thenon-reactive material may be selected from the group consisting of air,nitrogen, carbon dioxide, liquid hydrocarbon, liquid wax, oleaginousfluid, distilled water, polylactic acid, polyglycolic acid, plastic,solid wax, glycerin, alcohol, and any combination thereof. The frangiblecasing may comprise a material selected from the group consisting ofmetal, polymer, cellulosic material, ceramic material, and anycombination thereof. The reactive metal element may comprise a metalselected from the group consisting of magnesium, calcium, aluminum, tin,zinc, beryllium, barium, manganese, and any combination thereof. Thereactive metal element may comprise a metal alloy selected from thegroup consisting of magnesium-zinc, magnesium-aluminum,calcium-magnesium, aluminum-copper, and any combination thereof.

Provided are downhole devices comprising reactive metal elements. Anexample downhole device comprises a reactive metal element, and afrangible casing covering at least a portion of the reactive metalelement.

Additionally or alternatively, the downhole device may include one ormore of the following features individually or in combination. Thereactive metal element may be in the shape of a lattice. The reactivemetal element may be comprised of discrete pieces. The reactive metalelement may be disposed within a void space of the downhole device and anon-reactive material may be interspersed within the reactive metalelement while the reactive metal element is disposed within the voidspace. The non-reactive material may be selected from the groupconsisting of air, nitrogen, carbon dioxide, liquid hydrocarbon, liquidwax, oleaginous fluid, distilled water, polylactic acid, polyglycolicacid, plastic, solid wax, glycerin, alcohol, and any combinationthereof. The frangible casing may comprise a material selected from thegroup consisting of metal, polymer, cellulosic material, ceramicmaterial, and any combination thereof. The reactive metal element maycomprise a metal selected from the group consisting of magnesium,calcium, aluminum, tin, zinc, beryllium, barium, manganese, and anycombination thereof. The reactive metal element may comprise a metalalloy selected from the group consisting of magnesium-zinc,magnesium-aluminum, calcium-magnesium, aluminum-copper, and anycombination thereof.

Provided are systems for initiating the reaction of a reactive metalelement of a downhole device. An example system comprises a reactivemetal element, a frangible casing covering at least a portion of thereactive metal element, and a reaction-inducing fluid capable ofreacting with the reactive metal element to produce a reaction producthaving a second volume that is greater than the first volume.

Additionally or alternatively, the system may include one or more of thefollowing features individually or in combination. The reactive metalelement may be in the shape of a lattice. The reactive metal element maybe comprised of discrete pieces. The reactive metal element may bedisposed within a void space of the downhole device and a non-reactivematerial may be interspersed within the reactive metal element while thereactive metal element is disposed within the void space. Thenon-reactive material may be selected from the group consisting of air,nitrogen, carbon dioxide, liquid hydrocarbon, liquid wax, oleaginousfluid, distilled water, polylactic acid, polyglycolic acid, plastic,solid wax, glycerin, alcohol, and any combination thereof. The frangiblecasing may comprise a material selected from the group consisting ofmetal, polymer, cellulosic material, ceramic material, and anycombination thereof. The reactive metal element may comprise a metalselected from the group consisting of magnesium, calcium, aluminum, tin,zinc, beryllium, barium, manganese, and any combination thereof. Thereactive metal element may comprise a metal alloy selected from thegroup consisting of magnesium-zinc, magnesium-aluminum,calcium-magnesium, aluminum-copper, and any combination thereof.

The preceding description provides various examples of the apparatus,systems, and methods of use disclosed herein which may contain differentmethod steps and alternative combinations of components. It should beunderstood that, although individual examples may be discussed herein,the present disclosure covers all combinations of the disclosedexamples, including, without limitation, the different componentcombinations, method step combinations, and properties of the system. Itshould be understood that the compositions and methods are described interms of “comprising,” “containing,” or “including” various componentsor steps. The systems and methods can also “consist essentially of” or“consist of the various components and steps.” Moreover, the indefinitearticles “a” or “an,” as used in the claims, are defined herein to meanone or more than one of the element that it introduces.

For the sake of brevity, only certain ranges are explicitly disclosedherein. However, ranges from any lower limit may be combined with anyupper limit to recite a range not explicitly recited, as well as rangesfrom any lower limit may be combined with any other lower limit torecite a range not explicitly recited. In the same way, ranges from anyupper limit may be combined with any other upper limit to recite a rangenot explicitly recited. Additionally, whenever a numerical range with alower limit and an upper limit is disclosed, any number and any includedrange falling within the range are specifically disclosed. Inparticular, every range of values (of the form, “from about a to aboutb,” or, equivalently, “from approximately a to b,” or, equivalently,“from approximately a-b”) disclosed herein is to be understood to setforth every number and range encompassed within the broader range ofvalues even if not explicitly recited. Thus, every point or individualvalue may serve as its own lower or upper limit combined with any otherpoint or individual value or any other lower or upper limit, to recite arange not explicitly recited.

One or more illustrative examples incorporating the examples disclosedherein are presented. Not all features of a physical implementation aredescribed or shown in this application for the sake of clarity.Therefore, the disclosed systems and methods are well adapted to attainthe ends and advantages mentioned, as well as those that are inherenttherein. The particular examples disclosed above are illustrative only,as the teachings of the present disclosure may be modified and practicedin different but equivalent manners apparent to those skilled in the arthaving the benefit of the teachings herein. Furthermore, no limitationsare intended to the details of construction or design herein shown otherthan as described in the claims below. It is therefore evident that theparticular illustrative examples disclosed above may be altered,combined, or modified, and all such variations are considered within thescope of the present disclosure. The systems and methods illustrativelydisclosed herein may suitably be practiced in the absence of any elementthat is not specifically disclosed herein and/or any optional elementdisclosed herein.

Although the present disclosure and its advantages have been describedin detail, it should be understood that various changes, substitutionsand alterations can be made herein without departing from the spirit andscope of the disclosure as defined by the following claims.

What is claimed is:
 1. A method for initiating the reaction of areactive metal element of a downhole device comprising: introducing thedownhole device into a wellbore; wherein the downhole device comprisesthe reactive metal element; wherein the reactive metal element has afirst volume; wherein the reactive metal element is separated from areaction-inducing fluid by a frangible casing; removing the frangiblecasing; and contacting the reactive metal element with thereaction-inducing fluid to produce a reaction product having a secondvolume greater than the first volume.
 2. The method of claim 1, whereinthe reactive metal element is in the shape of a lattice.
 3. The methodof claim 1, wherein the reactive metal element is comprised of discretepieces.
 4. The method of claim 1, wherein the reactive metal element isdisposed within a void space of the downhole device and wherein anon-reactive material is interspersed within the reactive metal elementwhile the reactive metal element is disposed within the void space. 5.The method of claim 4, wherein the non-reactive material is selectedfrom the group consisting of air, nitrogen, carbon dioxide, liquidhydrocarbon, liquid wax, oleaginous fluid, distilled water, polylacticacid, polyglycolic acid, plastic, solid wax, glycerin, alcohol, and anycombination thereof.
 6. The method of claim 1, wherein the frangiblecasing comprises a material selected from the group consisting of metal,polymer, cellulosic material, ceramic material, and any combinationthereof.
 7. The method of claim 1, wherein the reactive metal elementcomprises a metal selected from the group consisting of magnesium,calcium, aluminum, tin, zinc, beryllium, barium, manganese, and anycombination thereof.
 8. The method of claim 1, wherein the reactivemetal element comprises a metal alloy selected from the group consistingof magnesium-zinc, magnesium-aluminum, calcium-magnesium,aluminum-copper, and any combination thereof.
 9. A downhole devicecomprising: a reactive metal element, and a frangible casing covering atleast a portion of the reactive metal element.
 10. The downhole deviceof claim 9, wherein the reactive metal element is in the shape of alattice.
 11. The downhole device of claim 9, wherein the reactive metalelement is comprised of discrete pieces.
 12. The downhole device ofclaim 9, wherein the reactive metal element is disposed within a voidspace of the downhole device and wherein a non-reactive material isinterspersed within the reactive metal element while the reactive metalelement is disposed within the void space.
 13. The downhole device ofclaim 12, wherein the non-reactive material is selected from the groupconsisting of air, nitrogen, carbon dioxide, liquid hydrocarbon, liquidwax, oleaginous fluid, distilled water, polylactic acid, polyglycolicacid, plastic, solid wax, glycerin, alcohol, and any combinationthereof.
 14. The downhole device of claim 9, wherein the frangiblecasing comprises a material selected from the group consisting of metal,polymer, cellulosic material, ceramic material, and any combinationthereof.
 15. The downhole device of claim 9, wherein the reactive metalelement comprises a metal selected from the group consisting ofmagnesium, calcium, aluminum, tin, zinc, beryllium, barium, manganese,and any combination thereof.
 16. The downhole device of claim 9, whereinthe reactive metal element comprises a metal alloy selected from thegroup consisting of magnesium-zinc, magnesium-aluminum,calcium-magnesium, aluminum-copper, and any combination thereof.
 17. Adownhole device comprising: a reactive metal element, a frangible casingcovering at least a portion of the reactive metal element, and areaction-inducing fluid capable of reacting with the reactive metalelement to produce a reaction product having a second volume that isgreater than the first volume.
 18. The system of claim 17, wherein thereactive metal element is in the shape of a lattice.
 19. The system ofclaim 17, wherein the reactive metal element is comprised of discretepieces.
 20. The system of claim 17, wherein the reactive metal elementis disposed within a void space of the downhole device and wherein anon-reactive material is interspersed within the reactive metal elementwhile the reactive metal element is disposed within the void space.